标题: | Impact of the surface recombination on InGaN/GaN-based blue micro-light emitting diodes |
作者: | Kou, Jianquan Shen, Chih-Chiang Shao, Hua Che, Jiamang Hou, Xu Chu, Chunshuang Tian, Kangkai Zhang, Yonghui Zhang, Zi-Hui Kuo, Hao-Chung 光电工程学系 光电工程研究所 Department of Photonics Institute of EO Enginerring |
公开日期: | 10-六月-2019 |
摘要: | In this work, the size-dependent effect for InGaN/GaN-based blue micro-light emitting diodes (mu LEDs) is numerically investigated. Our results show that the external quantum efficiency (EQE) and the optical power density drop drastically as the device size decreases when sidewall defects are induced. The observations are owing to the higher surface-to-volume ratio for small mu LEDs, which makes the Shockley-Read-Hall (SRH) non-radiative recombination at the sidewall defects not negligible. The sidewall defects also severely affect the injection capability for electrons and holes, such that the electrons and holes are captured by sidewall defects for the SRH recombination. Thus, the poor carrier injection shall be deemed as a challenge for achieving high-brightness mu LEDs. Our studies also indicate that the sidewall defects form current leakage channels, and this is reflected by the current density-voltage characteristics. However, the improved current spreading effect can be obtained when the chip size decreases. The better current spreading effect takes account for the reduced forward voltage. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement |
URI: | http://dx.doi.org/10.1364/OE.27.00A643 http://hdl.handle.net/11536/152289 |
ISSN: | 1094-4087 |
DOI: | 10.1364/OE.27.00A643 |
期刊: | OPTICS EXPRESS |
Volume: | 27 |
Issue: | 12 |
起始页: | 0 |
结束页: | 0 |
显示于类别: | Articles |